Now Available for Public Comment: Notice of Proposed Rulemaking (NPRM) for FDAAA 801 and NIH Draft Reporting Policy for NIH-Funded Trials

Determine the Effects of Gene Differences and Voriconazole on Enzyme CYP2B6 Activity in the Liver in Healthy Volunteers

This study has been completed.
Information provided by (Responsible Party):
Zeruesenay Desta, Indiana University Identifier:
First received: April 12, 2010
Last updated: April 8, 2013
Last verified: April 2013

The purpose of this study is to see if administration of medicines and genetic differences affects the activity of a liver enzyme called CYP2B6 in healthy volunteers.

Condition Intervention
Drug: Efavirenz and voriconazole

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Endpoint Classification: Pharmacokinetics/Dynamics Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Screening
Official Title: Effect of Cytochrome P450 2B6 Genetic Polymorphism and Voriconazole on CYP2B6 Activity in Healthy Volunteers

Resource links provided by NLM:

Further study details as provided by Indiana University:

Primary Outcome Measures:
  • Measure CYP2B6 activity in vivo, using the metabolism and pharmacokinetics of efavirenz as a probe. [ Time Frame: 17 days ] [ Designated as safety issue: No ]

Enrollment: 60
Study Start Date: March 2010
Study Completion Date: April 2013
Primary Completion Date: April 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: CYP2B6
CYP2B6*1/*1 , CYP2B6*1*6 and CYP2B6*6*6
Drug: Efavirenz and voriconazole
In phase 1 day 1 (control phase) a single 100mg dose of efavirenz will be administered. In phase 2 (voriconazole pretreatment phase), the subject will be pretreated with voriconazole (400mg twice daily on phase 2 day 8 and then 200mg twice daily for the next consecutive 8 days. In phase 3 (efavirenz plus voriconazole phase), the subject will receive on phase 3 day 10 100mg single dose of efavirenz along with 200mg of voriconazole twice daily.
Other Names:
  • Efavirenz
  • Voriconazole

Detailed Description:

The investigators will test the hypothesis that CYP2B6 genetic variants that show effects in vitro also influence the in vivo activity of CYP2B6 and its responsiveness to metabolic inhibition, using the metabolism of efavirenz (100 mg dose) as a marker of activity. The metabolism and pharmacokinetics of efavirenz will be determined in a total of 60 healthy volunteers with CYP2B6*1/*1, CYP2B6*1*6 and CYP2B6*6*6 at baseline (control) and after pretreatment with voriconazole.


Ages Eligible for Study:   18 Years to 55 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Male or female subject between 18 and 55 years of age.
  • Healthy individuals without any significant medical conditions as determined by a screening performed at University.
  • Adherence to the study dietary and medication restrictions.
  • Willingness to refrain from smoking or use of tobacco or marijuana one week before the start of the study and until completion of the study which will be a total of 17 days.
  • Ability to commit the time requested for this study.

Exclusion Criteria:

  • Underweight (weighs less than 50kg or 110lb) or over weight [body mass index (BMI) greater than 32].
  • Drug or alcohol abuse (more than 3 alcoholic drinks per day on a regular basis).
  • History of intolerance or allergic reaction (e.g. rash) to efavirenz and/or voriconazole.
  • Significant health conditions such heart, gastrointestinal disorders, liver, or kidney diseases that may be exacerbated during the course of the study.
  • History or current psychiatric illness (e.g. depression, anxiety, or nervousness).
  • History or current eye sight disturbances (e.g. blurred vision).
  • Serious infection within the last 2 weeks.
  • Blood donation within the past two months.
  • Screening results that do not fall in a healthy range.
  • Regularly taking prescriptions (except hormonal agents, e.g. oral contraceptives), over-the-counter, herbal or dietary supplements, and alternative medications and are unable or unwilling to stop taking them one week before and during the study periods.
  • Female with a positive pregnancy test.
  • Female breastfeeding.
  • Females of child-bearing potential who are unable or unwilling to either practice abstinence or use appropriate birth control up until the study completion, which will take a total of 17 days.
  • Participation in a research study involving intensive blood sampling and/or have use study drugs in the last two months.
  • Employed or student under supervision of any of the investigators of this study.
  • Inability to state a good understanding of this study including risks and requirements, and inability to follow the rules of this study.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01104376

United States, Indiana
Indiana University
Indianapolis, Indiana, United States, 46202
Sponsors and Collaborators
Indiana University
Principal Investigator: Zeruesenay Desta, PhD IU Department of Medicine/Division of Clinical Pharmacology
  More Information

No publications provided

Responsible Party: Zeruesenay Desta, Associate Professor of Medicine, Indiana University Identifier: NCT01104376     History of Changes
Other Study ID Numbers: 0808-16, R01GM078501
Study First Received: April 12, 2010
Last Updated: April 8, 2013
Health Authority: United States: Institutional Review Board

Keywords provided by Indiana University:
Cytochrome P450
Healthy volunteers

Additional relevant MeSH terms:
14-alpha Demethylase Inhibitors
Anti-Infective Agents
Anti-Retroviral Agents
Antifungal Agents
Antiviral Agents
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Nucleic Acid Synthesis Inhibitors
Pharmacologic Actions
Reverse Transcriptase Inhibitors
Therapeutic Uses processed this record on November 27, 2014